The present invention relates to a high-speed three-way solenoid valve for pressurized fluid, such as compressed air circuits.
Three-way solenoid valves are particularly useful for pneumatic circuits requiring exhaust of the fluid, e.g. from the control chamber of an actuating cylinder. On such valves, the response time of the moving element in relation to the control signal is extremely important, both when opening and closing the valve, in that it is this which determines the maximum operating frequency of the valve.
On one known type of three-way solenoid valve, the moving element is controlled by a piston having a minimum response time of about 8-10 ms, which is obviously insufficient for applications requiring a response time of about one millisecond.
Three-way valves are also known comprising a servo and secondary valve, wherein the moving element is controlled by a servomechanism. These, however, are invariably highly complex and expensive.